Process and apparatus for ascertaining the hardness of metal parts



E. SCHNEIDER. PROCESS AND APPARATUSFOR ASCERTAINING THE HARDNESS 0F MET AL PARTS.

Patented Sept. 28, 1920.

4 SHEETS-SHEET I E. SCHNEIDER.

PROCESS AND APPARATUS FOR ASCERTAINING THE HARDNESS 0F METAL PARTS. APPLICATION FILED AUG-2|, 1918.

1,354,21 A PatentedSept. 28,1920.

4 SHEETS-SHEET 2.

sgg "E l'zoveiciow iE. SCHNEIDER. PROCESS AND APPARATUS FOR ASCERTAINING THE HARDNESS 0F METAL PARTS. APPLICATION FILED AUG-21, i918.

.1 ,354',2 1 6. Patented Sept. 28, 1920.

4 SHEETS-SHEET 3.

v E. SCHNEIDER- PROCESS AND APPARATUS FOR ASCERTALNING THE HARDNESS 0F METAL PARTS APPLICATION FILED AUG-21,1918- I 4 SHEETSSHEET 4- mwaaaaam /L Z 2 .I x M n M I 552.5%;

W Md'M EUGENE SCHNEIDER, OF PARIS, FRANCE, ASSIGNOR T0 SCHNEIDER &; CI

FRANCE, A LIMITED JOINT-fi-TOCK COMPANY OF FRANCE.

PATENT OFFICE.

15., OF PARIS,

rnoonss AND APPARATUS roe ASCERTAINING THE HARDNESS or METAL PARTS.

Specification of Letters Patent.

Patented Sept. 28, 1920.

Application filed August 21, 1918. Serial No. 250,862.

To all whom it may concern Be it known that I, EUGENE SCHNEIDER, citizen of the French Republic,,residing at 42 Rue dAnjou, Paris, France, have invents ed certain new and useful Improvements in Processes and Apparatus for Ascertaining the Hardness of Metal Parts, of which the following is a specification.

Hitherto, for the purpose of ascertaining the hardness of a metal part, and more particularly the hardness of shells or other hollow articles, use is generally made of the method known as Brinells method which consists substantially in indenting the surface of the article to be tested, at a varying point, by means of a hard body such as a steel ball, and in measuring the dimensions of the indentation.

Experience and observations of the ap plicant have shownthat this method of as-.

certaining the hardness is not satisfactory and gives only very incomplete results; for instance in particular this method does not give any indication relating to the greater or less degree of homogeneity of the metal in the mass of the article the hardness of which it is desired to ascertain.

The present invention has for its object to provide an improved process and apparatus which will allow of remedying the above drawbacks in a manner which will be suincient for practical purposes.

The improved process consists essentially in producing one or more indentations by simultaneous and practically equal pressures in two opposite surfaces of. the article. The simultaneous pressures are therefore caused to act under identical conditions of pressure, temperature and duration of indentation, and at two opposite points including between them the thickness of the article, the hardness of which it is desired to ascertain before tempering, after tempering, or at any other moment of a heat treatment. The examination of the simultaneous indentations will furnish, in addition to the absolute indication given by their dimensions, a comparison between the hardness at two opposite points, and consequently a very valuable indication as to the greater or less degree of homogeneity of the metal in the region where the test has been made.

An apparatus for carrying into effect this improved process consists essentially of a kind of tongs or pincers whose shorter arms form aws. adapted to receive alternately an indenting body, such as a ball, and a device for reproducing said indentation, such as a cue containlng a lump of lead or other plastic material.

The invention comprises an. apparatus constituting a practical form of the said pincers for ascertaining the hardness of shells and other hollow articles.

Figure -1 is a sectional elevation of an apparatus for ascertaining the hardness of an article of any desired profile.v

Fig. 2 is a partial section on the line 11-11 of Fig. 1.

Figs. 3 to 6 illustrate an apparatus for applying the improved process for the purpose of ascertaining the hardness of a hollow article, such as for instance a shell.

Fig. 3 is a side elevation.

Fig. l is a plan.

Fig. 5 is a vertical section on the line VV of F ig.'4t.

Fig. 6 is a section on the line VIVI of Fig.

Figs. 7 and 8 are respectively a vertical section and a partial plan of a modification of the apparatus.

Referring first to Figs. 1 and 2, A is an axle mounted in a suitable support B; on this axle are rotatably mounted the two members-(3 C and DD of a tongs or pincers. At the end of each of the shorter arms C, D, there may be mounted a removable indenting device consisting for instance of a ball 6 held in a small holder E adapted to be screwed in a corresponding internal screw-thread in the arm of the pincers. lVhen the simultaneous indentations have been impressed into the article F to be tested, it is an easy matter to remove the ball holders E-e and to replace them by dies, that is to say, holders similar to E but bearing a plate of plastic material, such as lead.

The simultaneous and practically equal pressures applied at two opposite points 7", j, that inclose between them the thickness of the article F, are produced by moving the ends of the longer arms C D of the pincers closer together. This movement may be effected for instance by means of the mechanism shown.

G, H are sleeves journaled'by means of trunnion pins 9, h, respectively between forks formed on the ends of the arms C D.

j The sleeve G is internally screw-threaded,

whereas the'sleeve H has a pla n bore. A

is guided at its lower end 111 the spindle I sleeve H and engages with its screw-threaded'upper end in the nut-like sleeve The spindle I is prevented from moving longitudinally in the sleeve H by means of stop collars 2', i and unscrewing the spindle I in the nut-like sleeve G.

It will be readily perceived that the indentationsproduced at two opposite points f, 7'} of the article being tested, are produced with one. and the same apparatus under identical conditions of pressure, tempera 1 ture and duration of indentation ofthe intested.

In the construction form of the apparatus shown in Figs. 3 to 6 which illustrate an apparatus for applying the improved process for testing the hardness of a-hollow article, suchas a shell, one .of the jaws of'the pincers is carried by an arm C so shaped as to be capable of entering the hollow article, that is to say in the present example, or passing through the hole in the nose of the shell F. This arm C while being sufficiently strong, may have a slight degree of springiness; it is. formed on or carried by a bracket K mounted on a bed L. It is combined with a cradle M for supporting the shell to be tested. The axis of this cradle-is located in a longitudinal axial plane ofthe arm C. The said cradle may be formed on a stem m slidabletin afoot plate M which is in its turn slidable in the bed L in the longitudinal axial plane of the arm G. M is a spring bearing atone end against the underside of a shoulder on the platform M and at its other end against the footplate M This spring is calibrated in sucha manner that when the cradle'is brought to the desired point, the said spring will approximately balance the action of'the weight of the shell F upon the jaw formed on the end of the armC. Y The other jaw of the tongs or pincers is constructed as follows: N is a screw to the end of which there can be alternately fixed the ball-holder E. or the die-holder. This screw ismovable in a nut 0 formed at an intermediate point of a'lever P located in a in the framing of the apparatus; The force required for producing the simultaneous in- J is a hand-wheel. for screwing dentations, is applied at th'eopposite end or at any other suitable point of the lever P by anyknown means. a

By way of example the drawing shows a simple means consistin'gin suspending near the free end of the lever P, a'rod Q provided with a retaining collar or shoulder 9, upon which a variable number of heavy disks R can be engaged.

The lever P may be guided between uprights'S. Between these uprights there may be located a retractable support T. This support may be constituted for-instance by a plate mounted on the end of a rack t worlring between plain supports t and a pinion t loose on an axle pin 16 carried by the said upirightsS. Y V

Normally the action of the weights R will be balanced by the support T which is maintained in engagement by'an actuating pinion T fixed to a ratchet. wheel T with which a pawlT is adapted to be engaged.

In order to raise the lever P, the pinion T will be operated by means of a hand-wheel the preceding apparatus designed more particularly for ascertammg the hardness of the inner bottom end of a hollow. article, such for instance the base of a projectile.

In this example, the projectile or other hollow article to'be tested, is supported by a platform M carried by rods m slidable in a foot-plate. M which maybe fixed at a varying distance from the bed L, M are springs bearing against the foot-plate 1M and the platform they serve to'balance practically the weight ofrthe article under test. One of theball holders E is mounted on the end of an arm C fixed to the footpl'ate M in such a manner thatthe said ball holder E shall be capable of projecting through a central orifice in the said footplate. The other ball .holder is mounted on the lower end of an arm N which is pivoted by means of spin at toa screw T. This screw N is, as in the preceding example, adapted to work in a nut 0 provided at'an intermediate point of a leverP. This lever P is, as in the example shown in Figs. 3 to 6, fulcrumed at one endon anaxle pin 10 and is adapted to receive at its other end the effort required for producing the simul taneous indentations.

The apparatus is completed; by a simple means which allows of bringing different regions of the bottom of the hollow article between the two jaws of the pincers, the latter occupying an eccentric position relatively to the axis of the said article as shown. To a clamping ring V located at a suitable point in the length of the projectile there is jointed a lever V adapted to bear upon the outer surface of the shell. The power required for moving the shell around its axis by means of the lever V is reduced by arranging the latter to bear by means of a roller V upon a circular track V located on the framing of the apparatus. The shell is guided vertically for instance by means of a suitably calibrated sleeve X.

One or more guiding rollers X whose axles are mounted on the framing are provided for the purpose of guiding the shell so as to keep it upright for centering it in the sleeve X in placing the shell upon the supporting platform.

After the external and internal indentations have been produced simultaneously by means of the improved apparatus, they may be reproduced in relief in a plastic material, by dismounting the ball holders Ee and replacing them by dies, that is to say, by similar holders bearing a plate of lead or other plastic material. The pressure for effecting the simultaneous moldings of the two indentations may be produced by means of the same weight R on the lever P, acting if desired for a shorter time, or by means of a suitably reduced weight.

It is to be understood that the improved process and apparatus for producing and' then observing simultaneous indentations formed in varying regions of a test article under identical conditions of pressure, temperature and duration of indentation, while furnishing on one hand valuable indications as to the constitution of the test article, are also capable of furnishing at the same time indications as to the apparatus for tempering or treating, or as to the nature of the metal; if the operations are carried out with a standard test piece or on a verified test piece. This invention can thus furnish simple and practical means for regulating a manufacture, because it allows of modifying according to the indications obtained, the apparatus for tempering or treating, as well as the nature of the metal.

Having now described my invention what I claim as new and desire to secure by Letters latent is 1. The process for testing the hardness of metal plates, walls, and the like which consists in subjecting the same at opposite points on opposite sides of the plate or wall to be tested to the simultaneous action of indentation means impelled by equal forces and adapted to produce indentations increasing in dimension with increase of penetration and then measuring the dimensions of the indentations to determine the degree of homogeneity of the metal at.the portion tested.

2. In an apparatus for testing the hardness of a test article by producing indentations in opposite surfaces of said article, the combination of a pair of tongs, a removable holder in the jaw of each tong, an indenting body, such as a steel ball, in said holder, and mechanism acting upon the tails of said tongs for pressing said holders containing said indenting bodies against opposite surfaces of the test article.

3. In an apparatus for testing the hard ness of a test article by producing indentations in opposite surfaces of said article, the combination of a pair of tongs, a removable holder in the jaw of each tong, an indenting body, such as a steel ball, in said holder, an internally screw-threaded sleeve on the tail of one tong, and a plain bore sleeve on the tail of the other tong, a partly screwthreaded spindle engaging said sleeves, and a device for rotating said spindle so as to move the indenting jaws toward each other.

4. In an apparatus for testing the hardness of metal walls and the like by produc ing indentations in opposite surfaces ofsaid wall, the combination of oppositely disposed holders for receiving hardness testing ele ments, said testing elements being adapted to be simultaneously operated by equal forces to produce indentations increasing in dimension with increase of penetration, and meansfor moving one of said holders into testing position with respect to the other.

In testimony whereof I have affixed my signature in presence of two witnesses.

EUGENE SCHNEIDER.

Witnesses ANDRE Mosrionnn, JOHN F. S'IMONS. 

